CN103983397A - Three-dimensional sensing measurement system and method based on vector decomposition and synthesis mechanism - Google Patents

Abstract

The invention belongs to the field of detection technologies and sensor technologies and particularly relates to a three-dimensional sensing measurement system and method based on vector decomposition and a synthesis mechanism. According to vector decomposition and the synthesis mechanism, the three-dimensional mechanical quantity or vector components of a measured direction are converted to achieve three-dimensional measurement by measuring the three-dimensional decomposition amount different from a measured target vector. A special cone three-dimensional sensing unit designed in this way achieves three-dimensional (longitudinal direction, vertical direction and transverse direction) mechanical measurement. According to the three-dimensional sensing measurement system and method, multiple cone structures are integrated, the nanotechnology is adopted, an artificial mechanical sensitive 'skin' can be prepared, and the system and method can also be applied to measurement of three-dimensional turbulent flow velocity characteristics in flow dynamics. The three-dimensional sensing measurement system and method are a new means for three-dimensional mechanical measurement or three-dimensional turbulent flow velocity.

Description

A kind of three-dimensional sensing measurement system and method based on resolution of vectors and synthesis mechanism

Technical field

The invention belongs to detection technique and sensor technical field, be specifically related to a kind of three-dimensional sensing measurement system and method based on resolution of vectors and synthesis mechanism.

Background technology

Three-dimensional mechanical or flow velocity measure the limitation that is subject to sensor construction, method and volume, are the bottlenecks of restriction sensor intelligent always.

For the depth of investigation of three-dimensional mechanical or fluid-velocity survey, depend on to a great extent the level of measuring technology or sensor development, particularly microminiaturized and high sensitivity, high reliability are three difficult points of this technology.Wherein, microminiaturized key is how to realize 3 D stereo to detect and obtain corresponding three-dimensional mechanical eigenwert.

At present, a peacekeeping dimension sensor has had more kind, as: various piezoresistive pressure sensors, cantilever beam stress sensor.By by quick power good both direction beam with right-angled intersection form, form two-dimentional mechanical meaurement model and have been reported and apply.But the measurement of the three-dimensional vector method of synchronous three-dimensional mechanical is not reported, but three-dimensional measurement technology has very important scientific meaning for the technology of association area, the development of equipment.For example: when robot fish movement, be subject to the impact in water body flow field very large, in order correctly to export advancing drive power and steering wheel strategy, need the direction of perception current and the state of power and whirlpool, but, due to the profile of fish and the constraint of sports system, be difficult to the above-mentioned information of direct perception, can, by detecting the parameter of different vectors or vector, obtain the parameter of paying close attention to thus.Such as, the pin of artificial intelligence robot, need to understand the state of kiss the earth again, the distribution of decision-making driving force and overall balance, also can realize vector quantization by mechanism of the present invention and measure.In the time of the three-dimensional turbulent fluctuation flow velocity of measuring in two-phase flow, requiring is affecting under minimum background former fluidised form, and the turbulent fluctuation flow velocity of perception three-dimensional obtains turbulent inner structure and kinematic behavior accurately.

Summary of the invention

The present invention solves the existing technical matters of prior art; According to the decomposition of vector and synthesis mechanism, design the three-dimensional sensing unit of special cone, be different from the three-dimensional exploded amount of measured target vector by measurement, realize three-dimensional (longitudinal, vertical, horizontal three directions) mechanics and measured.By integrated multiple vertebral body structures of the present invention, adopt nanometer technique, can prepare artificial mechanics sensitivity " skin ", also can in any fluid, realize the measurement to three-dimensional turbulent fluctuation flow speed characteristic.The present invention measures and is also significant for the three-dimensional mechanical of various structures, is the new tool that a kind of three-dimensional mechanical or three-dimensional turbulent fluctuation flow velocity measure.

Above-mentioned technical matters of the present invention is mainly solved by following technical proposals:

A three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, is characterized in that, comprising:

A three-dimensional sensing unit of cone: apply a constant current source to the three-dimensional sensing unit of cone by a sensor excitation source, for stressed the three-dimensional detecting at current induction is converted to Voltage-output signal, the three-dimensional sensing unit of this cone be one cone-shaped, comprise: stressed bead and three are for supporting three support bars of stressed bead, one end of three support bars comes together in the top of cone, the center of collecting as future sensor stressed or be subject to the centre of sphere of the stressed bead of water impact; The other end of three support bars is separately fixed at the one end with the quick beam of silicon power of the corresponding measurement stress of support bar body of rod positioned vertical, and the other end of three quick beams of silicon power is clamped on central supported holder respectively; On described three quick beams of silicon power, be equipped with four for experiencing the silicon pressure drag sheet of water flow pressure, a Hui Sitong full bridge measurement circuit of described four silicon pressure drag sheets composition, constant current source applies a continuous current to this Hui Sitong full bridge measurement circuit, is output as the voltage signal of variation;

A signal condition unit: comprise and connect successively San road difference feeble signal instrument amplification circuit and No. three filtering circuits, for the voltage signal of the variation of three-dimensional cone sensing unit output is amplified and filtering;

Data acquisition and signal processing unit: adopt DSP as microprocessor, its inner integrated A D modular converter, for data acquisition and the conversion of signal after filtering, voltage signal after conversion is through analysis and the processing of DSP, can calculate the actual flow velocity of current, i.e. longitudinal flow velocity u, vertical flow velocity v, transverse flow speed w;

Computing machine and information handling system: be connected with signal processing unit with data acquisition by RS485 or CAN bus and WI-FI module, for to carrying out data acquisition, analysis, calculating and processing;

A fixation kit: for the three-dimensional sensing unit of fixing cone and for detecting under water;

A power supply unit: power to whole system.

At above-mentioned a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, the angle of three support transmission rods and cone center line is θ, three quick beams of silicon power are symmetrical, and angle is each other 120 °, and are 90 ° with the angle of support bar respectively.

At above-mentioned a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, described fixation kit comprises a L shaped and inner body for hollow, the three-dimensional sensing unit of described cone is fixed on body bottom, body bottom one end opening, and openend outer wall is wedge shape; Muzzle one end outer wall and body bottom interior wall adapt, and insert body bottom open end and be arranged on the muzzle inwall collar by one muzzle is stuck in to body bottom opening place; Muzzle other end tube wall is obliquely installed so that opening dwindles gradually; The central supported holder of the three-dimensional sensing unit of cone is fixed on the collar, and stressed bead extend out to outside muzzle other end opening, and the bore of described muzzle other end opening is greater than the diameter of stressed bead.

At above-mentioned a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, the laying method of four silicon pressure drag sheets in the three-dimensional sensing unit of described cone in the quick beam of each silicon power is: the quick beam of silicon power is using N-type silicon as substrate, be cut into simultaneously and detect the needed shape of silicon beam, as stress, the responsive detecting element of strain signal; On this N-type silicon beam, diffusion p type impurity, forms resistor stripe, and according to silicon beam positive and negative stress area under sensor force environment, is arranged to Hui Sitong full bridge measurement circuit, R in circuit ₁, R ₂, R ₃, R ₄the resistance value of corresponding silicon pressure drag sheet 1,2,3,4 respectively; Because the distance dependent of the strain of foil gauge size and power effect, so silicon pressure drag sheet is attached to the surface nearer apart from stiff end, i.e. silicon pressure drag sheet R ₁and R ₃be parallel to the quick beam of silicon power and be positioned over negative strain district, R ₂and R ₄vertical and the quick beam of silicon power is positioned over normal strain district; In the time that the cantilever silicon beam end at silicon pressure drag electric bridge place is stressed, silicon pressure drag sheet R ₂, R ₄be subject to the pulling force of the quick beam of Parallel Si power to produce normal strain, resistance increases; Silicon pressure drag sheet R ₁, R ₃be subject to the acting force inwardly pushing perpendicular to the quick beam of silicon power both sides and produce negative stress, resistance reduces.

At above-mentioned a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, high-speed data acquisition also comprises with disposal system the attitude detection unit and the environmental monitoring unit that are connected with microprocessor DSP simultaneously; Described attitude detection unit adopts gyroscope, for arrangement attitude and self vibration detection of sensor; Described environmental monitoring unit comprises fluid temperature sensor, atmosphere temperature transducer and is arranged on system self temperature sensor of the housing outer wall of body, and this environmental monitoring unit is for detection of the environment of sensor place detected fluid.

Decompose and the three-dimensional sensing method for measurement of synthesis mechanism based on Mechanics Vector, it is characterized in that, based on to give a definition: the angle of three support transmission rods and cone center line is θ, and flow action is in the power of stressed bead the power decomposing on support bar 1,2,3 is respectively f ₁, f ₂, f ₃, its direction is along the direction of support bar 1,2,3; Decomposition by vector, with synthetic, can obtain at the component of x, y, z direction; component in x direction: f _x=(f ₁+ f ₂cos60 °-f ₃cos60 °) sin θ

component in y direction: f _y=(f ₂-f ₃) sin θ cos60 °

component in z direction: f _z=(f ₁+ f ₂+ f ₃) cos θ

Due to the size that can be calculated instantaneous velocity is: (wherein, ρ is the density of detected fluid, and s is the lifting surface area that rill acts on bead);

: longitudinal flow velocity u, vertical flow velocity v, transverse flow speed w that current are corresponding are respectively:

$u=v_z=\left|\stackrel{\→}{v}\right|\frac{f_z}{\sqrt{f_x^2+f_y^2+f_z^2}}$

$v=v_x=\left|\stackrel{\→}{v}\right|\frac{f_x}{\sqrt{f_x^2+f_y^2+f_z^2}}$

$w=v_y=\left|\stackrel{\→}{v}\right|\frac{f_y}{\sqrt{f_x^2+f_y^2+f_z^2}};$

Comprise the following steps:

Step 1, current flow through the three-dimensional sensing unit of cone, the three-dimensional sensing unit of cone is subject to the excitation from high precise current source, flow velocity u, the v of three directions of induction detected fluid, the adaptability to changes that w produces in three directions of cone three-dimensional structure x, y, z, be converted to electric signal signal now by the strain of the quick beam of silicon power on measuring bridge fainter, need to carry out the conditioning of signal by three tunnel difference feeble signal instrument amplification circuit and filtering circuit, then send into data acquisition and signal processing unit and carry out data acquisition, analysis, calculating and processing;

Step 2, all data and measurement result are by processing and the analysis of DSP, completed with background computer and information handling system and completed data transmission and communicate by letter by RS485 or CAN bus and WIFI module, making this sensor can be that basic turbulent flow is measured and analytic system with computer communication composition data storehouse on the one hand; Also comprise a WIFI module and complete wireless telecommunications, by WIFI and mobile phone A pp program, realize parameter setting and the data of cell phone and check fast; All the circuit of measurement system is embedded in the metal cavitg of sensor, accomplishes to shield completely, guarantees that sensor reaches the highest signal to noise ratio (S/N ratio).

At above-mentioned a kind of three-dimensional sensing method for measurement based on Mechanics Vector decomposition and synthesis mechanism, in described step 2, calculate the power f on support bar 1,2,3 by the voltage signal changing ₁, f ₂, f ₃concrete grammar be: define four for experiencing resistance value that the silicon pressure drag sheet of water flow pressure is corresponding respectively: R ₁, R ₂, R ₃, R ₄, the current value of constant current source is I _a, the silicon pressure drag sheet of the required acquisition of F is subject to external force, can draw output voltage U according to Wheatstone bridge computing method _o;

$U_O=\frac{R_2{R}_4-R_1{R}_3}{R_1+R_2+R_3+R_4}{I}_a$

In the time of bridge balance, resistance initial value meets: therefore have:

? $U_O=\frac{4\mathrm{\μ}{R}_2^0{R}_4^0}{R_1+R_2+R_3+R_4}{I}_a\·F$ Or $U_O=\frac{4\mathrm{\μ}{R}_1^0{R}_3^0}{R_1+R_2+R_3+R_4}{I}_a\·F$

Wherein, k is the gage factor of silicon pressure drag sheet, and S is the lifting surface area of silicon pressure drag sheet, and E is elastic modulus.

Therefore, tool of the present invention has the following advantages: 1. according to the decomposition of vector and synthesis mechanism, design the three-dimensional sensing unit of special cone, be different from the three-dimensional exploded amount of measured target vector by measurement, realized three-dimensional (longitudinal, vertical, horizontal three directions) mechanics and measured; 2. in any fluid, can realize the measurement to three-dimensional turbulent fluctuation flow speed characteristic; 3. by integrated multiple vertebral body structures of the present invention, adopt nanometer technique, can prepare artificial mechanics sensitivity " skin "; 4. measure and be also significant for the three-dimensional mechanical of various structures.

Brief description of the drawings

The physical arrangement of the three-dimensional sensing unit of cone that Fig. 1 designs for the present invention.

The stressed decomposing schematic representation of the cone three-dimensional structure fluid-velocity survey that Fig. 2 designs for the present invention.

Fig. 3 is the present invention's quick girder construction of silicon power used and stress measurement principle schematic.

Fig. 4 is the present invention's favour stone used full bridge measurement circuit.

Fig. 5 is the three-dimensional sensing unit structural drawing of the designed sensor of the present invention.

Fig. 6 is the present invention's sensor measurement system used block diagram.

The three-dimensional turbulent fluctuation flow sensor overall construction drawing that Fig. 7 designs for the present invention.

The three-dimensional turbulent fluctuation flow sensor outside drawing that Fig. 8 designs for the present invention.

Embodiment

Below by embodiment, and by reference to the accompanying drawings, technical scheme of the present invention is described in further detail.

Embodiment:

Below in conjunction with above drawings and Examples, the principle to foregoing invention content, implementation method, implementation process are specifically described.

One, the vector of three-dimensional cone structure power decomposes and composition principle.

According to the vector characteristic of three-dimensional mechanical model, need to be under to the condition of tested flow field disturbance minimum, build and structural model is measured in design.Utilize hydrodynamic force to meet the characteristic of linear vector, by pyrometric cone body structure, detect core sensing unit as three-dimensional mechanical, design as shown in Figure 1.One of three force rods of cone comes together in the top of cone, the center of collecting is as the centre of sphere of the stressed spheroid of sensor current (3mm diameter), the another side of three support bars is separately fixed at the end with the quick beam of silicon power of the corresponding measurement stress of body of rod positioned vertical, the other end of three quick beams of silicon power is clamped on central supported holder respectively, each stress measurement beam is realized by the pressure drag semi-girder of a stress sensitive, stressed ball design is placed in the outside of sensor housing, directly tested current are met in front, because this measurement ball is placed in sensor housing foremost, so to the disturbance minimum of tested water.

When the stressed bead of sensor is subject to after flow action, be delivered to the flexible silicon beam of strained silicon resistance by supporting transmission rod, and then electric signal corresponding to corresponding velocity vector value convert to, reflect the principle of time dependent flow turbulence flow velocity.

As shown in Figure 2, the angle of three support transmission rods and cone center line is θ to the stressed exploded pictorial of three-dimensional turbulent fluctuation fluid-velocity survey, and three quick beams of silicon power are symmetrical, and angle is each other 120 °, and is 90 ° with the angle of support bar respectively.Flow action is in the power of stressed bead according to resolution of vectors and composition principle, the power decomposing on support bar 1,2,3 is respectively f ₁, f ₂, f ₃, its direction is along the direction of support bar 1,2,3, and each support bar can decompose again as follows along the power of x, y, z direction (x, y, z direction defines as shown in Figure 2):

Support bar 1 resolution of force:

$f_x^1=f_1\sin \mathrm{\θ},f_y^1=0,f_z^1=f_1\cos \mathrm{\θ}$

Support bar 2 resolution of force:

Support bar 3 resolution of force:

Can obtain thus, component in x, y, z direction is:

component in x direction: f _x=(f ₁+ f ₂cos60 °-f ₃cos60 °) sin θ

component in y direction: f _y=(f ₂-f ₃) sin θ cos60 °

component in z direction: f _z=(f ₁+ f ₂+ f ₃) cos θ

From fluid mechanics, the power of fluid becomes quadratic relationship with flow velocity, can be expressed as:

$f\∝{\left|\stackrel{\→}{v}\right|}^2$ (formula 1)

The above analysis and formula 1, the size that can obtain instantaneous velocity is:

$\left|\stackrel{\→}{v}\right|=k_m\sqrt[4]{f_x^2+f_y^2+f_z^2}$ (formula 2)

In formula 2, ρ is the density of detected fluid, and s is the lifting surface area that rill acts on bead, k _mactual value can be demarcated and draw by experiment, the present invention in sensor construction design, θ=10 °.

direction vector with direction consistent, can obtain thus, corresponding longitudinal flow velocity, vertical flow velocity, transverse flow speed u, v, w are respectively:

$u=v_z=\left|\stackrel{\→}{v}\right|\frac{f_z}{\sqrt{f_x^2+f_y^2+f_z^2}}$ (formula 3)

$v=v_x=\left|\stackrel{\→}{v}\right|\frac{f_x}{\sqrt{f_x^2+f_y^2+f_z^2}}$ (formula 4)

$w=v_y=\left|\stackrel{\→}{v}\right|\frac{f_y}{\sqrt{f_x^2+f_y^2+f_z^2}}$ (formula 5)

According to formula 3, formula 4 and formula 5, measure and can be calculated the flow velocity sequence of a time period { u}, { v}, { w}, calculates and process this time series, gets final product to obtain mean flow rate and the turbulent fluctuation flow velocity of all directions.

Two, the strain measurement principle of the quick beam of silicon power in cone structure.

In sensitive structure unit design, will be using N-type silicon as substrate, be cut into simultaneously and detect the needed shape of the quick beam of silicon power, as stress, strain signal sensitive element.On this N-type silicon beam, diffusion p type impurity, forms resistor stripe, and according to the quick beam of silicon power positive and negative stress area under sensor force environment, is arranged to full-bridge, forms the detecting element of sensor, and this element is a beam type, the vibrational system of one degree of freedom.When the kinetic energy of current while being applied on flexible member by the thin transmission rod of cone, be converted into potential energy f _x, flexible member meets with stresses and strain occurs, and becomes and mv through the quick cell translation of exertin ²proportional signal.In the time that angular displacement is very micro-, applied external force and θ are linear.Because the rigidity of the flexible member adopting is very large, so in the time measuring, in fact the angular displacement of generation very little, thereby the vibration equation of vibrating elements can be reduced to following linear differential equation:

$\frac{d^{2}x}{{\mathrm{dt}}^2}+2D\frac{\mathrm{dx}}{\mathrm{dt}}+{\mathrm{\ω}}_{0}x=\frac{F}{m}=f$

In formula 6, the quality that m is vibrational system, h is resistance coefficient, K is elasticity coefficient, for the free vibration angular frequency of system, for attenuation coefficient.

Although flow turbulence is not that periodically, in the time domain of growing at any one, the fluctuating velocity sum of pulsing up and down at the mean flow rate of water velocity should be zero.The pulsation part of the flow velocity in this region can be thought to be made up of many harmonic waves, is expressed as follows:

(formula 7)

In formula 7, ω _ifor being applied to the angular frequency of the current on sensor, n is the number of times of the higher hamonic wave composition of can not ignore in current.In the situation that laboratory sink is tested, the frequency spectrum of current is regarded as below 100Hz conventionally.In silt carrying flow, its frequency range is more offset to the low region of frequency along with the increasing of silt content.The general solution form that can obtain thus vibration equation is:

$x\left(t\right)=e^{-\mathrm{Dt}}(C_1{e}^{t\sqrt{D^2-{{\mathrm{\ω}}_0}^2}}+C_2{e}^{-t\sqrt{D^2-{{\mathrm{\ω}}_0}^2}})+\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{X}_i\sin ({\mathrm{\ω}}_{i}t+{\mathrm{\φ}}_i)$ (formula 8)

In formula 8, Section 1 represents the decay free vibration of system, after testing, decays to rapidly zero; Section 2 represents under external force, the forced vibration that system produces.In linear system, its Changing Pattern is consistent with applied external force.Suitably select damping, can make phase shift and frequency proportional, thereby unlikely generation phase distortion.

In the time that spheroid front end freely bears the impact of current and pressure, current and turbulent stress can be passed through to three supports of cone by perception, be delivered to the silicon pressure drag stress sensitive beam of support foot, the quick beam of silicon power is realized the synchronous stress and strain that current instantaneous velocity impacts that detects in real time, and the quick stress beam measuring principle of silicon power as shown in Figure 3.

By diffusion technique, integrated stress sensitive silicon pressure drag sheet full-bridge on silicon beam, 4 silicon pressure drag sheets on the quick beam of silicon power form Hui Sitong full bridge measurement circuit as shown in Figure 4.The quick beam stress of silicon power produces strain and stress, according to silicon pressure drag sheet stress bridge design principle, and when the cantilever silicon beam end at silicon pressure drag sheet electric bridge place is stressed, pressure drag sheet R ₂, R ₄be subject to the pulling force of the quick beam of Parallel Si power to produce normal strain, resistance increases; Pressure drag sheet R ₁, R ₃be subject to the acting force inwardly pushing perpendicular to the quick beam of silicon power both sides and produce negative stress, resistance reduces.Therefore, can draw from the bridge diagram shown in Fig. 4, the suffered acting force of the quick beam of silicon power is larger, and stress levels is larger, output voltage U ₀just larger.

Calculate the power f on support bar 1,2,3 by the voltage signal changing ₁, f ₂, f ₃concrete grammar be: define four for experiencing resistance value that the silicon pressure drag sheet of water flow pressure is corresponding respectively: R ₁, R ₂, R ₃, R ₄, the current value of constant current source is I _a, can draw output voltage U according to Wheatstone bridge computing method _o.

$U_O=\frac{R_2{R}_4-R_1{R}_3}{R_1+R_2+R_3+R_4}{I}_a$ (formula 9)

In the time that silicon pressure drag sheet is subject to external force F generation strain, the relation of its strain stress and power F can be expressed as:

$\mathrm{\ϵ}=\frac{F}{\mathrm{SE}}$ (formula 10)

In formula 10, S is the lifting surface area of silicon pressure drag sheet, and E is elastic modulus (constant);

Due to gage factor K and the resistance initial value R of silicon pressure drag sheet ⁰the relation relatively changing can be expressed as:

(wherein, Δ R is increased resistance value) (formula 11)

If the resistance of silicon pressure drag sheet after external force F effect produces strain is R _f, calculate according to formula 10 and formula 11:

$R_F=(1+\frac{K}{\mathrm{SE}}F)R_0$ (formula 12)

Due to for constant, calculate for simplifying, establish r so _fcan be expressed as again:

R _f=(1+ μ F) R ₀(formula 13)

In Wheatstone bridge calculates, R ₁, R ₂, R ₃, R ₄do the used time being subject to external force F, strain stress relation meets formula 13.Because R ₁, R ₃produce negative strain, R ₂, R ₄produce normal strain, that is:

$\left.\begin{array}{c}{R}_{1F}=(1-\mathrm{\μF})R_1^0\\ R_{2F}=(1+\mathrm{\μF})R_2^0\\ R_{3F}=(1-\mathrm{\μF})R_3^0\\ R_{4F}=(1+\mathrm{\μF})R_4^0\end{array}\right\}$ (formula 14)

In the time there is not strain, when bridge balance, resistance initial value meets:

$R_1^0{R}_3^0=R_2^0{R}_4^0$ (formula 15)

Formula (14) and formula (15) substitution formula 9, can obtain:

$U_O=\frac{4\mathrm{\μ}{R}_2^0{R}_4^0}{R_1+R_2+R_3+R_4}{I}_a\·F$ Or $U_O=\frac{4\mathrm{\μ}{R}_1^0{R}_3^0}{R_1+R_2+R_3+R_4}{I}_a\·F$ (formula 16)

By formula 16, can calculate the power f on support bar 1,2,3 ₁, f ₂, f ₃.

The signal of three quick beams of silicon power, through modulate circuit, filtering circuit, AD conversion, data acquisition and conversion, data processing and analysis, obtains the hydrodynamics characteristic respective signal of corresponding three quick beam space directions of silicon power.Tri-directions of u, v, w of the current that detect from wish due to the direction of three quick beams of silicon power are different, therefore one of key of this technology is that measured mechanical quantity is changed with the space between corresponding three-dimensional flow vector.

Three, the design of the three-dimensional sensing unit of cone.

Taking vector transfer principle as the three-dimensional sensitive structure unit of the cone that design of basis, need the signal of conversion to have the corresponding rate of flow of fluid acting force of u, v, tri-directions of w and atmospheric temperature, detected fluid temperature, the interior temperature of sensor body etc.The physical design figure of sensing unit is as shown in above Fig. 1, stressed bead (diameter 3mm) is settled at cone top, the bottom of three support bars is vertically connected to the quick beam of cantilever silicon power, the stress measurement of changing on corresponding three spaces, strain through the quick beam of silicon power is converted to electric signal, reaches the object that measures the suffered three-dimensional mechanical vector of bead.

Four, the whole measurement system design the present invention relates to.

The measurement system of three-dimensional turbulent fluctuation flow sensor is mainly made up of power supply unit, sensor excitation source, the three-dimensional sensing unit of cone, signal condition unit, data acquisition and signal processing unit, environmental detection unit, attitude detection unit and computing machine and information handling system.The principle of work of measurement system is illustrated as shown in Figure 6.Power supply unit is mainly each submodule unit of system and powers, the three-dimensional sensing unit of cone is subject to the excitation from high precise current source, the flow velocity u of three directions of induction detected fluid, v, w is at cone three-dimensional structure x, y, the adaptability to changes that tri-directions of z produce, strain by the quick beam of silicon power on measuring bridge is converted to electric signal, signal is now fainter, need to carry out the conditioning of signal by three tunnel difference feeble signal instrument amplification circuit and filtering circuit, then send into data acquisition and signal processing unit and carry out data acquisition, analyze, calculate and process.This unit is the core of measurement system, adopts dsp chip that volume little, micro-power consumption, function are strong as microprocessor, completes three-dimensional turbulent fluctuation flow sensor required signals collecting and processing.Meanwhile, DSP processing unit also control environment detecting unit and attitude detection unit, the temperature survey and the various position and attitude that complete detected fluid environment are measured.All data and measurement result are by processing and the analysis of DSP, completed with background computer and information handling system and completed data transmission and communicate by letter by RS485 (or CAN bus), WIFI, making this sensor can be that basic turbulent flow is measured and analytic system with computer communication composition data storehouse on the one hand.In addition, in this measuring system, design embeds WIFI module and completes wireless telecommunications, by WIFI and mobile phone A pp program, realizes parameter setting and the data of cell phone and checks fast.All the circuit of measurement system is embedded in the metal cavitg of sensor, accomplishes to shield completely, guarantees that sensor reaches the highest signal to noise ratio (S/N ratio).

The structural design of the whole three-dimensional turbulent fluctuation flow sensor five, the present invention relates to.

According to feature and the feature of set corresponding three-dimensional turbulent fluctuation flow velocity, design the sensing unit of special cone three wimble structures as sensor, embed microprocessing by the modern times, complete vector and transform, reach synchronization, digitizing, the intelligent object that detects three-dimensional flow.Adopt vector to design the general structure of sensor as the new method of sensor research, in design, adopt the sensing unit of cone three wimble structures as sensor, this unit is connected with the main supporter of sensor, and formation can complete the three-dimensional turbulent fluctuation flow sensor that different depth is measured.As shown in Figure 7, three-dimensional turbulent fluctuation flow sensor outside drawing as shown in Figure 8 for the one-piece construction of designed sensor.As can be seen from Figure 8, the body supports of sensor adopts the sickle structure of streamline, reduces as far as possible the disturbance to measurement point flow field, measures stressed bead and is placed in sensor foremost, directly bears the acting force of tested current.

Cone three-dimensional structure has that volume is little, good stability, mechanical model meet resolution of vectors and the feature of synthetic demand.On the basis of this mechanical structure model, except stressed bead is placed in sensor foremost, meet outside the acting force of current, sensing unit (comprise the quick beam of silicon power and support transmission rod) is realized waterproof and is stoped otherwise masterpiece to be used in the interference producing on the quick beam of silicon power within being all integrated in housing.In order to insulate and the not conduction of influence power, in shell cavity, by injecting the flexible silica gel of modification, can ensure reliable measurement, also can prevent silt and current scour sensing unit.

The design of three-dimensional turbulent fluctuation flow sensor data acquisition and signal processing unit, mainly comprise the collection of DSP multi-channel high-speed data, spectrum analysis processing, digital filtering, vector transforms numeral, and temperature self-compensation measures bridge excitation power supply, amplification, conditioning and the sampling of feeble signal, the circuit such as A/D conversion, data storage.Carry out data communication by RS-485 bus (or CAU bus), WIFI, realize synchronous data collection, processing, output, the analysis of multiple turbulent fluctuation flow sensors, distributedly distribute and lay the foundation along the three-dimensional turbulent fluctuation flow rate detection of cross-sectional distribution and analysis along experimental tank axis for building.

Six, technical performance index.

The three-dimensional turbulent fluctuation flow velocity of the present invention's development measures prototyping system, will reach following index:

(1) measuring object: three-dimensional turbulent fluctuation flow velocity, the water temperature etc. of space point in detected fluid;

(2) applicability: clear water, low (maximum sediment concentration can reach 300kg/m containing husky water and high sand-carrying water ³);

(3) environment for use temperature: 0～55oC;

(4) sound the depth of the water: <50cm tank;

(5) resolution: 1cm/s;

(6) range: <5m/s;

(7) instrument performance is stable, and repeatability is better than 1%;

(8) can on-the-spot measure fast the distribution pattern of each point flow velocity along the depth of water, make researcher can judge in time current flow pattern.

Specific embodiment described herein is only to the explanation for example of the present invention's spirit.Those skilled in the art can make various amendments or supplement or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.

Specific embodiment described herein is only to the explanation for example of the present invention's spirit.Those skilled in the art can make various amendments or supplement or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.

Claims (7)

1. the three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism, is characterized in that, comprising:

A three-dimensional sensing unit of centrum: apply a constant current source to the three-dimensional sensing unit of centrum by a sensor excitation source, for stressed the three-dimensional detecting at current induction is converted to Voltage-output signal, the three-dimensional sensing unit of this centrum is a centrum shape, comprise: stressed bead and three are for supporting three support bars of stressed bead, one end of three support bars comes together in the top of cone, the center of collecting as future sensor stressed or be subject to the centre of sphere of the stressed bead of water impact; The other end of three support bars is separately fixed at the one end with the quick beam of silicon power of the corresponding measurement stress of support bar body of rod positioned vertical, and the other end of three quick beams of silicon power is clamped on central supported holder respectively; On described three quick beams of silicon power, be equipped with four for experiencing the silicon pressure drag sheet of water flow pressure, a Hui Sitong full bridge measurement circuit of described four silicon pressure drag sheets composition, constant current source applies a continuous current to this Hui Sitong full bridge measurement circuit, is output as the voltage signal of variation;

A signal condition unit: comprise and connect successively San road difference feeble signal instrument amplification circuit and No. three filtering circuits, for the voltage signal of the variation of three-dimensional centrum sensing unit output is amplified and filtering;

Data acquisition and signal processing unit: adopt DSP as microprocessor, its inner integrated A D modular converter, for data acquisition and the conversion of signal after filtering, voltage signal after conversion is through analysis and the processing of DSP, can calculate the actual flow velocity of current, i.e. longitudinal flow velocity u, vertical flow velocity v, transverse flow speed w;

Computing machine and information handling system: be connected with signal processing unit with data acquisition by RS485 or CAN bus and WI-FI module, for to carrying out data acquisition, analysis, calculating and processing;

A fixation kit: for the three-dimensional sensing unit of fixing centrum and for detecting under water;

A power supply unit: power to whole system.

2. a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism according to claim 1, it is characterized in that, the angle of three support transmission rods and cone center line is θ, three quick beams of silicon power are symmetrical, angle is each other 120 °, and is 90 ° with the angle of support bar respectively.

3. a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism according to claim 1, it is characterized in that, described fixation kit comprises a L shaped and inner body for hollow, the three-dimensional sensing unit of described centrum is fixed on body bottom, body bottom one end opening, and openend outer wall is wedge shape; Muzzle one end outer wall and body bottom interior wall adapt, and insert body bottom open end and be arranged on the muzzle inwall collar by one muzzle is stuck in to body bottom opening place; Muzzle other end tube wall is obliquely installed so that opening dwindles gradually; The central supported holder of the three-dimensional sensing unit of centrum is fixed on the collar, and stressed bead extend out to outside muzzle other end opening, and the bore of described muzzle other end opening is greater than the diameter of stressed bead.

4. a kind of three-dimensional sensing measurement system based on resolution of vectors and synthesis mechanism according to claim 1, it is characterized in that, the laying method of four silicon pressure drag sheets in the three-dimensional sensing unit of described centrum in the quick beam of each silicon power is: the quick beam of silicon power is using N-type silicon as substrate, be cut into simultaneously and detect the needed shape of silicon beam, as stress, the responsive detecting element of strain signal; On this N-type silicon beam, diffusion p type impurity, forms resistor stripe, and according to silicon beam positive and negative stress area under sensor force environment, is arranged to Hui Sitong full bridge measurement circuit, R in circuit ₁, R ₂, R ₃, R ₄the resistance value of corresponding silicon pressure drag sheet 1,2,3,4 respectively; Because the distance dependent of the strain of foil gauge size and power effect, so silicon pressure drag sheet is attached to the surface nearer apart from stiff end, i.e. silicon pressure drag sheet R ₁and R ₃be parallel to the quick beam of silicon power and be positioned over negative strain district, R ₂and R ₄vertical and the quick beam of silicon power is positioned over normal strain district; In the time that the cantilever silicon beam end at silicon pressure drag electric bridge place is stressed, silicon pressure drag sheet R ₂, R ₄be subject to the pulling force of the quick beam of Parallel Si power to produce normal strain, resistance increases; Silicon pressure drag sheet R ₁, R ₃be subject to the acting force inwardly pushing perpendicular to the quick beam of silicon power both sides and produce negative stress, resistance reduces.

5. one according to claim 1, based on resolution of vectors and synthesis mechanism three-dimensional sensing measurement system, is characterized in that, high-speed data acquisition also comprises with disposal system the attitude detection unit and the environmental monitoring unit that are connected with microprocessor DSP simultaneously; Described attitude detection unit adopts gyroscope, for arrangement attitude and self vibration detection of sensor; Described environmental monitoring unit comprises fluid temperature sensor, atmosphere temperature transducer and is arranged on system self temperature sensor of the housing outer wall of body, and this environmental monitoring unit is for detection of the environment of sensor place detected fluid.

6. utilize decomposing and the three-dimensional sensing method for measurement of synthesis mechanism based on Mechanics Vector described in claim 1, it is characterized in that, based on to give a definition: the angle of three support transmission rods and cone center line is θ, and flow action is in the power of stressed bead the power decomposing on support bar 1,2,3 is respectively f ₁, f ₂, f ₃, its direction is along the direction of support bar 1,2,3; Decomposition by vector, with synthetic, can obtain at the component of x, y, z direction;

component in x direction: f _x=(f ₁+ f ₂cos60 °-f ₃cos60 °) sin θ

component in y direction: f _y=(f ₂-f ₃) sin θ cos60 °

component in z direction: f _z=(f ₁+ f ₂+ f ₃) cos θ

Due to the size that can be calculated instantaneous velocity is: wherein, ρ is the density of detected fluid, and s is the lifting surface area that rill acts on bead;

: longitudinal flow velocity u, vertical flow velocity v, transverse flow speed w that current are corresponding are respectively:

$u=v_z=\left|\stackrel{\&RightArrow;}{v}\right|\frac{f_z}{\sqrt{f_x^2+f_y^2+f_z^2}}$

$v=v_x=\left|\stackrel{\&RightArrow;}{v}\right|\frac{f_x}{\sqrt{f_x^2+f_y^2+f_z^2}}$

$w=v_y=\left|\stackrel{\&RightArrow;}{v}\right|\frac{f_y}{\sqrt{f_x^2+f_y^2+f_z^2}};$

Comprise the following steps:

Step 1, current flow through the three-dimensional sensing unit of centrum, the three-dimensional sensing unit of cone is subject to the excitation from high precise current source, flow velocity u, the v of three directions of induction detected fluid, the adaptability to changes that w produces in three directions of cone three-dimensional structure x, y, z, strain by the quick beam of silicon power on measuring bridge is converted to electric signal, signal is now fainter, need to carry out the conditioning of signal by three tunnel difference feeble signal instrument amplification circuit and filtering circuit, then send into data acquisition and signal processing unit and carry out data acquisition, analysis, calculating and processing;

Step 2, all data and measurement result are by processing and the analysis of DSP, completed with background computer and information handling system and completed data transmission and communicate by letter by RS485 or CAN bus and WIFI module, making this sensor can be that basic turbulent flow is measured and analytic system with computer communication composition data storehouse on the one hand; Can also, by WIFI and mobile phone A pp program, realize parameter setting and the data of cell phone and check fast on the other hand.

7. a kind of three-dimensional sensing method for measurement based on Mechanics Vector decomposition and synthesis mechanism according to claim 6, is characterized in that, in described step 2, calculates the power f on support bar 1,2,3 by the voltage signal changing ₁, f ₂, f ₃concrete grammar be: define four for experiencing resistance value that the silicon pressure drag sheet of water flow pressure is corresponding respectively: R ₁, R ₂, R ₃, R ₄, the current value of constant current source is I _a, the silicon pressure drag sheet of the required acquisition of F is subject to external force, can draw output voltage U according to Wheatstone bridge computing method _o;

$U_O=\frac{R_2{R}_4-R_1{R}_3}{R_1+R_2+R_3+R_4}{I}_a;$

In the time of bridge balance, resistance initial value meets: therefore have:

$U_O=\frac{4\mathrm{\&mu;}{R}_2^0{R}_4^0}{R_1+R_2+R_3+R_4}{I}_a\&CenterDot;F$ Or $U_O=\frac{4\mathrm{\&mu;}{R}_1^0{R}_3^0}{R_1+R_2+R_3+R_4}{I}_a\&CenterDot;F;$

Wherein, k is the gage factor of silicon pressure drag sheet, and S is the lifting surface area of silicon pressure drag sheet, and E is elastic modulus.